There are 2 secrets in One Shot, One Kill. (1/2) Locate the building bungalow where Vasquez was in (and escaped from after the failed snipe). Put the building on your forward-left and turn around 180 ...

There is 1 secret in Dangerous Grounds. (1/1) After passing the first stealth section, you get a cut-scene of a knife kill. When you start off in the next zone, locate the radio transmission tower and ...